Is there a way in Java to get the result from this mathematical expression:
String code = "5+4*(7-15)";
In other hand what's the best way to parse an arithmetic expression?
You can pass it to a BeanShell bsh.Interpreter
, something like this:
Interpreter interpreter = new Interpreter(); interpreter.eval("result = 5+4*(7-15)"); System.out.println(interpreter.get("result"));
You'll want to ensure the string you evaluate is from a trusted source and the usual precautions but otherwise it'll work straight off.
If you want to go a more complicated (but safer) approach you could use ANTLR (that I suspect has a math grammar as a starting point) and actually compile/interpret the statement yourself.
i recently developed a expression parser and released it under the apache license. you can grab it at http://projects.congrace.de/exp4j/index.html
hope that helped
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